FREEHOLD — A Red Bank teenager whose driving while intoxicated caused the death of one passenger and seriously injured another last year, admitted his responsibility in superior court on Thursday.

Adam F. Sofio, 19, pleaded guilty to vehicular homicide and assault by auto as part of a negotiated agreement, the Monmouth County Prosecutor’s Office announced.

According to authorities, Sofio was driving his 1992 Honda Accord on Cooper Avenue in Middletown last Feb. 27, when at approximately 2:05 a.m. Sofio lost control of the vehicle and it skidded off the road, hitting a tree on a residential property. The Honda, the prosecutor’s office said, split in two from the force of the collision, causing massive injuries to the front seat passenger.

That passenger, Paul Bradley, 18, was pronounced dead at the scene.

John Vogel, also 18 and from Middletown, was sitting in the rear seat and was seriously injured, with emergency responders taking him to Jersey Shore University Medical Center, Neptune, for treatment.

Appearing before Judge Anthony J. Mellaci on Thursday, Sofio admitted to drinking a substantial amount of alcohol, with authorities adding his blood alcohol level, taken two hours after the crash, registered .314 percent.

According to the state’s Office of the Attorney General, a blood alcohol concentration of 0.08 percent or greater would indicate a driver was legally intoxicated.

Sofio told the judge he had also ingested marijuana earlier and had been driving more than three times faster than the posted 25 miles per hour on Cooper Road, the prosecutor’s office said.

Sofio had initially been arrested last May 9, and was released from the Monmouth County Correctional Institution, Freehold, after post a $200,000 bail, according to authorities.

The prosecutor’s office said vehicular homicide is a third degree offense and a conviction could carry with it a penalty of up to 10 years in state prison. The assault by auto is also a third degree crime and could result in up to five years behind bars. But because of the negotiated plea agreement, the county prosecutor will recommend that Sofio be sentence to a six-year incarceration, when Sofio appears before Mellaci again on May 18.

The vehicular homicide offense is also subject to the No Early Release Act, meaning Sofio would have to serve a minimum of 85 percent of the sentence before being considered for parole, the prosecutor said.